Hongyan Zhang, Yetan Shi, Lifang Hu
Background Current therapeutic options for scalp seborrheic dermatitis (SSD) remain suboptimal, highlighting the demand for more effective and safe treatment strategies. Objective To investigate the efficacy and underlying mechanisms of a novel 7.5% five-acid compound formulation for the treatment of SSD. Methods A total of 319 patients diagnosed with SSD at the dermatology outpatient clinic were enrolled. All patients received four sessions of scalp compound acid therapy and were included in efficacy and safety analyses. A subgroup of 30 male participants from the 319-patient cohort underwent scalp sampling before and after treatment for combined microbiomic and lipidomic detection. Meanwhile, 10 matched male SSD patients who did not received compound acid therapy were enrolled as the control group for multi-omics analyses. Results All 319 SSD patients presented marked relief of scalp erythema, scaling and pruritus after repeated compound acid treatment, with only 6 individuals experiencing temporary mild scalp irritation after the initial treatment. Integrated microbiomic and lipidomic analyses were restricted to a male subcohort (30 treated patients and 10 matched untreated male SSD controls). Within this male subgroup, the relative abundance of the genus Staphylococcus and the genus Malassezia were significantly lowered post-treatment. And the observed lipid alterations may be linked to changes in antioxidant response, inflammatory signaling and fatty acid metabolic pathways. Lipidomic profiling suggests that compound acid peeling may rebalance scalp lipid profiles, accompanied by elevated levels of barrier-protective antioxidant phosphatidylcholines, reduced pro-inflammatory oxidized fatty acids, and altered core fatty acid biosynthesis pathways. Conclusion The topical scalp compound acid therapy effectively alleviates clinical symptoms in SSD patients and represents a promising novel therapeutic approach.